Conventional cough preparations containing an effective anti-tussive agent such as codeine have long been used for the symptomatic relief of coughs. However, codeine has various side effects which are undesirable.
Accordingly, the present invention relates to compositions of matter useful as pharmaceutical compositions having anti-tussive activity, and a method of treating warm-blooded animals affected by coughs or bronchoconstriction by administering an effective amount of the pharmaceutical compositions of the invention.
The problems of the prior art have been overcome by the present invention, which provides pharmaceutical compositions possessing anti-tussive activity, and a method of administering the same to warm-blooded animals, including humans. The active anti-tussive agent in accordance with the present invention is a quaternary ammonium compound represented by the following formula (I) and its pharmaceutically acceptable salts: 
wherein Y and E are independently selected from xe2x80x94CH2xe2x80x94R2 or: 
wherein R, R1 and R2 are independently selected from hydrogen, C1-C8 alkyl, C3-C8 alkoxyalkyl and C7-C12 aralkyl; and where R3, R4 and R5 are independently selected from bromine, chlorine, fluorine, carboxy, hydrogen, hydroxy, hydroxymethyl, methanesulfonamido, nitro, sulfamyl, trifluoromethyl, C2-C7 alkanoyloxy, C1-C6 alkyl, C1-C6 alkoxy, C2-C7 alkoxycarbonyl, C1-C6 thioalkyl, aryl and N(R6, R7) where R6 and R7 are independently selected from hydrogen, acetyl, methanesulfonyl and C1-C6 alkyl, An31  is the acid addition salt of a pharmaceutically acceptable acid or the anion from a pharmaceutically acceptable salt, and isolated enantiomeric, diastereomeric and geometric isomers thereof, and mixtures thereof, with the proviso that Y and E cannot both be xe2x80x94CH2xe2x80x94R2 in the same compound.